Card Range To Study

47 Cards in this Set

The DNA strand that has the same sequence as the mRNA and is related by the genetic code to the protein sequence that it represents.

coding strand (sense strand)

The DNA strand that is complementary to the sense strand, and acts as the template for synthesis of mRNA.

antisense strand (template strand)

Enzymes that synthesize RNA using a DNA template (formally described as DNA-dependent RNA polymerases).

RNA polymerases

A region of DNA where RNA polymerase binds to initiate transcription.

promoter

The position on DNA corresponding to the first base incorporated into RNA.

startpoint

A sequence of DNA that causes RNA polymerase to terminate transcription.

terminator (t)

The sequence between sites of initiation and termination by RNA polymerase; it may include more than one gene.

transcription unit

Sequences in the opposite direction from expression.

upstream

Sequences proceeding farther in the direction of expression.

downstream

The original unmodified RNA product corresponding to a transcription unit.

primary transcript

The stages of transcription up to synthesis of the first bond in RNA. This includes binding of RNA polymerase to the promoter and melting a short region of DNA into single strands.

initiation

The stage in a macromolecular synthesis reaction (replication, transcription, or translation) when the nucleotide or polypeptide chain is extended by the addition of individual subunits.

elongation

A separate reaction that ends a macromolecular synthesis reaction (replication, transcription, or translation), by stopping the addition of subunits, and (typically) causing disassembly of the synthetic apparatus

termination

The RNA polymerase form that is competent to initiate transcription. It consists of the four subunits of the core enzyme (a2ßß') and s factor.

holoenzyme (complete enzyme)

The complex of RNA polymerase subunits needed for elongation. It does not include additional subunits or factors that may be needed for initiation or termination.

core enzyme

The subunit of bacterial RNA polymerase needed for initiation; it is the major influence on selection of promoters.

sigma factor

Any random sequence of DNA that is bound by the core RNA polymerase when it is not engaged in transcription.

loose binding site

The stage of initiation of transcription when RNA polymerase causes the two strands of DNA to separate to form the "transcription bubble."

open complex

The binding of RNA polymerase to DNA in the formation of an open complex (when the strands of DNA have separated).

tight binding

The complex in initiation of transcription that consists of RNA polymerase and DNA and a dinucleotide that represents the first two bases in the RNA product.

ternary complex

It describes a process in which RNA polymerase starts transcription but terminates before it has left the promoter. It then reinitiates. Several cycles may occur before the elongation stage begins.

abortive initiation

Sequences in which many examples of a particular nucleic acid or protein are compared and the same individual bases or amino acids are always found at particular locations

conserved sequences

An idealized sequence in which each position represents the base most often found when many actual sequences are compared.

consensus sequence

The consensus sequence centered about 10 bp before the startpoint of a bacterial gene. It is involved in melting DNA during the initiation reaction.

-10 sequence

The consensus sequence centered about 35 bp before the startpoint of a bacterial gene. It is involved in initial recognition by RNA polymerase.

-35 sequence

A mutation in a promoter that decreases the rate of transcription.

down mutation

A mutation in a promoter that increases the rate of transcription.

up mutation

A technique for identifying the site on DNA bound by some protein by virtue of the protection of bonds in this region against attack by nucleases.

footprinting

A set of loci activated in response to an increase in temperature (and other abuses to the cell). All organisms have them. Their products usually include chaperones that act on denatured proteins.

heat shock genes

Genes that are transcribed before the replication of phage DNA. They code for regulators and other proteins needed for later stages of infection.

early genes

Phage genes that are regulated by the proteins coded by early genes. Some proteins coded bythem catalyze replication of the phage DNA; others regulate the expression of a later set of genes.

middle genes

Genes transcribed when phage DNA is being replicated. They code for components of the phage particle.

late genes

A sequence of events, each of which is stimulated by the previous one. In transcriptional regulation, as seen in sporulation and phage lytic development, it means that regulation is divided into stages, and at each stage, one of the genes that are expressed codes for a regulator needed to express the genes of the next stage.

cascade

The generation of a spore by a bacterium (by morphological conversion) or by a yeast (as the product of meiosis).

sporulation

The period of normal growth and division of a bacterium. For a bacterium that can sporulate, this contrasts with the sporulation phase, when spores are being formed

vegetative phase

A pathway in which a phosphate group is passed along a series of proteins.

phosphorelay

A sequence of DNA that causes RNA polymerase to terminate transcription.

terminator (t)

A mechanism of transcriptional control in which termination is prevented at a specific terminator site, allowing RNA polymerase to read into the genes beyond it.

antitermination

It occurs at transcription or translation when RNA polymerase or the ribosome, respectively, ignores a termination signal because of a mutation of the template or the behavior of an accessory factor.

readthrough

Terminators that are able to terminate transcription by bacterial RNA polymerase in the absence of any additional factors.